things haven't changed much in 400 years...
This mask was designed to fight against the Miasma theory. This theory of disease believed that people got sick from “bad air”, and so what this mask’s long nose was designed to do was the wearers would put pleasant smelling herbs and light then on fire to prevent Miasma from being inhaled by the wearer by “cleansing” the “bad air”.
The mask had glass openings in the eyes and a curved beak shaped like a bird’s beak with straps that held the beak in front of the doctor’s nose. The mask had two small nose holes and was a type of respirator which contained aromatic items. The beak could hold dried flowers (including roses and carnations), herbs (including mint), spices, camphor, or a vinegar sponge. The purpose of the mask was to keep away bad smells, known as miasma, which were thought to be the principal cause of the disease, before it was disproved by germ theory. Doctors believed the herbs would counter the “evil” smells of the plague and prevent them from becoming infected.
LOL they weren't far off with this notion actually there was definitely something in the air. There were reports of volcanic eruptions at the time and lots of witnesses to noxious smelling 'mists' which killed plants/crops and animals. If anything this old mask might have worked better than the pathetic face nappies they wear now against pollution in China etc.
and those masks were quite stylish